1. | \(Z\) protons and \(A-Z\) neutrons |
2. | \(Z\) protons and \(A\) neutrons |
3. | \(A\) protons and \(Z-A\) neutrons |
4. | \(Z\) neutrons and \(A-Z\) protons |
The mass number of a nucleus is:
1. | always less than its atomic number. |
2. | always more than its atomic number. |
3. | sometimes equal to its atomic number. |
4. | sometimes less than and sometimes more than its atomic number. |
1. | \({}_{34}^{74}\mathrm{Se}, {}_{31}^{71}\mathrm{Ca}\) | 2. | \({}_{42}^{92}\mathrm{Mo}, {}_{40}^{92}\mathrm{Zr}\) |
3. | \({}_{38}^{81}\mathrm{Sr}, {}_{38}^{86}\mathrm{Sr}\) | 4. | \({}_{20}^{40}\mathrm{Ca}, {}_{16}^{32}\mathrm{S}\) |
The mass of an -particle is:
1. | less than the sum of masses of two protons and two neutrons. |
2. | equal to the mass of four protons. |
3. | equal to the mass of four neutrons. |
4. | equal to the sum of masses of two protons and two neutrons. |
The mass of a \({}_{3}^{7}\mathrm{Li}\) nucleus is \(0.042\) u less than the sum of the masses of all its nucleons. The binding energy per nucleon of the \({}_{3}^{7}\mathrm{Li}\) nucleus is near:
1. \(4.6\) MeV
2. \(5.6\) MeV
3. \(3.9\) MeV
4. \(23\) MeV
1. | \( m_3=\left|m_1-m_2 \right|\) | 2. | \( m_3<\left ( m_1+m_2 \right ) \) |
3. | \( m_3>\left ( m_1+m_2 \right ) \) | 4. | \( m_3=\left ( m_1+m_2 \right ) \) |
1. | \(0.0305\) J | 2. | \(0.0305\) erg |
3. | \(28.4\) MeV | 4. | \(0.061\) u |
1. | \(\dfrac{8 A + 2}{A + 1}\) | 2. | \(\dfrac{8 A - 2}{A + 1}\) |
3. | \(\dfrac{8 A - 1}{A + 1}\) | 4. | \(\dfrac{8 A}{A + 1}\) |
A nucleus with mass number \(240\) breaks into fragments each of mass number \(120.\) The binding energy per nucleon of unfragmented nuclei is \(7.6~\text{MeV}\) while that of fragments is \(8.5~\text{MeV}.\) The total gain in the binding energy in the process is:
1. \(804~\text{MeV}\)
2. \(216~\text{MeV}\)
3. \(0.9~\text{MeV}\)
4. \(9.4~\text{MeV}\)